548 The American Naturalist. [July, 
adaptations are determinate; they proceed in definite progres- 
sive lines. A short study of the child will disabuse any man, 
I think, of the “pure chance” theory. But the other theory 
which holds that consciousness makes adaptations and changes 
structures directly by its fiat, is contradicted by the psychology 
of voluntary movement (ref. 4, 6, 7). Consciousness can bring 
about no movement without having first an adequate experi- 
ence of that movement to serve on occasion as a stimulus to 
the innervation of the appropriate motor centers. “This point 
is no longer subject to dispute; for pathological cases show 
that unless some adequate idea of a former movement made 
by the same muscles, or by association some other idea which 
stands for it, can be brought up in mind the intelligence is 
helpless. Not only can it not make new movements; it can 
not even repeat old habitual movements. So we may say that 
intelligent adaptation does not create codrdinations; it only 
makes functional use of coérdinations which were alternatively 
present already in the creature’s equipment. Interpreting this 
in terms of congenital variations, we may say that the varia- 
tions which the intelligence uses are alternative possibilities of 
muscular movement” (ref. 4). So the only possible way that 
a really new movement can be made is by making the move- 
ments already possible so excessively and with so many varieties of 
combination, ete., that new adaptations may occur. 
5. The problem seems to me to duplicate the conditions — 
which led Darwin to the principle of natural selection. The 
alternatives before Darwin were “pure chance” or “special 
creation.” The law of “ overproduction with survival of the 
fittest ” came as the solution. So in this case. Letus take an 
example. Every child has to learn how to write. If he de- 
pended upon chance movements of his hands he would never 
learn how to write. But on the other hand, he can not write 
simply by willing to do so; he might will forever without 
effecting a “special creation” of muscular movement. What 
he actually does is to use his hand in a great many possible ways as 
near as he can to the way required ; and from these excessively pro- 
duced movements, and after excessively varied and numerous 
trials, he gradually selects and fixes the slight successes made 
